HELP!!! DROPPED MY EXTERNAL HARD DRIVE

I have a IBM 20GB laptop hard drive in an external case. I just picked it up and it slipped from my hand and the drive fell, while in its case on a carpeted floor from about 4 feet. Right after that I plugged it in and it started clicking. At the end of the day by dropping it on purpose from 6 inches and shakeing it, it spins up now fine with no clicking and I can hear the heads moving and the drive seeking but my computers don't recognize it. Is the drive broken or is the external case damaged? PLZ HELP!!! I just scanned the drive before I dropped it and IT HAD NO BAD SECTORS!!!! I NEED THIS DRIVE!!!!

Im gonna try it in a laptop because I think the enclosure is screwed up. I put in a 4.2 GB drive that I know spins up but has bad sectors and it just clicks. but if i do buy a new one, which I might not because this was one of my spares, I would get a 200GB SATA notebook drive for my new laptop (C2D @ 2.0GHZ, 2GB RAM, ATIx1400,120GB,DVD Burner, Bluetooth, wireless, remote, Inspiron E1505)

another thing about the drive I dropped. If i put a known Bad Hitachi 4.2 GB hard drive in the enclosure it clicks and the LED flashes red and green at the same time, if I put in the IBM, the one I dropped, it just clicks but the LED stays green as though the drive is working? any suggestions? And also, the Fujistu drive I have runs very cool, about 45 C in my laptop

Thanks for the replies, I am gonna try it out in a laptop and if it doesnt work, I might look into an other one. Instead of a HD, I might get a desktop HD (160GB) and 2GB RAM (OCZ @ 800MHz) to upgrade my XPS. I'll post back with the hard drive results